1. Field of the Invention
This device relates to multiple rotary fluid machines and more particularly, to multiple rotary fluid pumps and multiple rotary fluid motors.
2. Prior Art
In the prior art there exist rotary fluid pumps and rotary fluid motors.
Some embodiments of such pumps and motors employ a rotor which revolves within a chamber provided in a stator, and the rotor is provided with radially guided vanes which, revolve with the rotor and pass along a path between opposite curved faces of the stator chamber, as the vanes are held in positive engagement with the profile of the stator. Each chamber of the stator is provided with inlet and outlet ports.
Another embodiment of such pumps and motors employ a rotor provided with a groove with opposite curved faces defining plurality of lobes and depressions, and a stator ring inserted into the groove which together with the opposite depressions define a plurality of opposite alternate chambers, a plurality of sealing vanes extending through the ring and engaging with the outer and inner surface of the rotor groove, and fluid passages provided in the ring adjacent to the sealing vanes with alternate fluid passages connected together.
However, such fluid motors or pumps suffer from certain disadvantages. In particular, they are torque and flow restricted with respect to the operating speed.
Another major disadvantage of the prior art rotary machine is the great tendency for generating of pulsations.
The primary reason for the disadvantages of the prior art rotary fluid pumps and motors are the design limitations.
In particular, the vanes switch between a most upper position and a most recessed position during operation. As a result, the driving force radius changes and respectively the output torque for the motor's applications changes too. Furthermore, the volume of the inside chambers defer from the volume of the outside chambers. As a result, the generated flow for pump's application pulsates.
The greatest effect of the generated pulsations is a premature failure of the rotary machine and system, as well as a noise.
Another reason for speed, flow and torque restrictions of the prior art rotary machine is the restricted abruptness of the slope curve between two nearby opposite recessions. More particularly for a certain number of lobes, vanes and physical size of the rotary machine, the displacement depends on the volume defined by the recessions and the ring. An abrupt slope defines a larger volume. However, the abrupt slope restricts the operating speed and cause excessive wear of the vanes. Also it may cause breakage of the vanes because of the large front opposite force.
Consequently, the only alternative to obtain greater displacement capacities is to make the whole machine physically larger.
Generally, physically larger units have higher costs of manufacture, freight, installation, maintenance and handling.
Representative examples of such prior art rotary fluid machines are shown in the following United States patents:
______________________________________ 315,318 888,779 1,249,881 1,518,812 1,811,729 2,099,193 2,280,272 2,382,259 2,458,620 4,551,080 ______________________________________
Still further, the devices of the prior art have another disadvantage in their sliding seals. In particular, the sliding seals are not side pressure and wear compensated. Consequently, after the vanes and adjustment surfaces wear, the high pressure inner chambers and the low pressure outer chambers become at least partially interconnected and the efficiency of the rotary fluid machine will decrease until the machine finally ceases to operate.